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CALTHEK 650 mg TABLETS

This page is for general information. Consult a doctor for personal advice. Call emergency services if symptoms are severe.
About the medicine

How to use CALTHEK 650 mg TABLETS

Introduction

PACKAGE LEAFLET: INFORMATION FOR THE USER

Calthek 650 mg tablets

paracetamol

Read all of this leaflet carefully before you start taking this medicine because it contains important information for you.

Follow exactly the administration instructions of the medicine contained in this leaflet or as indicated by your doctor or pharmacist.

  • Keep this leaflet, as you may need to read it again.
  • If you need advice or more information, consult your pharmacist. If you experience side effects, consult your doctor or pharmacist, even if it is a side effect not listed in this leaflet. See section 4.
  • You should consult a doctor if it worsens or does not improve after 3 days with fever or 5 days with pain.

Contents of the package leaflet:

  1. What is Calthek and what is it used for
  2. What you need to know before you start taking Calthek
  3. How to take Calthek
  4. Possible side effects
  5. Storage of Calthek
  6. Contents of the pack and further information

1. What is Calthek and what is it used for

Paracetamol is effective in reducing pain and fever.

This medicine is used for the symptomatic relief of occasional mild or moderate pain, such as headache, dental, muscle (cramps) or back (lumbago) pain and in febrile conditions in adults and adolescents over 15 years of age.

2. What you need to know before you start taking

Do not take Calthek

  • If you are allergic to paracetamol or any of the other components of this medicine (listed in section 6).

Warnings and precautions

Do not take more than the recommended dose in section 3. How to take Calthek.

Avoid simultaneous use of this medicine with other medicines that contain paracetamol, such as flu and cold medicines, as high doses can lead to liver damage. Do not use more than one medicine that contains paracetamol without consulting your doctor.

If you have liver, kidney, heart, or lung disease, or have anemia (decrease in hemoglobin levels in the blood, due to or not due to a decrease in red blood cells), you should consult your doctor before taking this medicine.

When you are being treated with any medicine for epilepsy, you should consult your doctor before taking this medicine, as the efficacy of paracetamol may be decreased and hepatotoxicity may be increased, especially with high doses of paracetamol.

In chronic alcoholics, you should be cautious not to take more than 3 tablets of 650 mg of paracetamol in 24 hours.

Asthmatic patients sensitive to acetylsalicylic acid should consult their doctor before taking this medicine.

If the pain persists for more than 5 days, the fever for more than 3 days, or the pain or fever worsens or other symptoms appear, you should consult your doctor and reassess the clinical situation.

During treatment with Calthek, inform your doctor immediately:

If you have severe diseases, such as severe renal failure or sepsis (when bacteria and their toxins circulate in the blood, causing damage to organs), or if you have malnutrition, chronic alcoholism, or are also taking flucloxacillin (an antibiotic). A serious disease called metabolic acidosis (an anomaly in blood and fluids) has been reported in patients in these situations when paracetamol is used at regular doses for a prolonged period or when paracetamol is taken with flucloxacillin. The symptoms of metabolic acidosis may include: severe breathing difficulties with deep and rapid breathing, drowsiness, feeling of discomfort (nausea) and vomiting.

Interaction of Calthek with other medicines

Tell your doctor or pharmacist that you are taking, have recently taken, or may take any other medicine.

Paracetamol may interact with the following medicines:

  • Medicine to prevent blood clots: Oral anticoagulants (acenocoumarol, warfarin)
  • Medicines for treating epilepsy: Antiepileptics (lamotrigine, phenytoin or other hydantoins, phenobarbital, methylphenobarbital, primidone, carbamazepine)
  • Medicines for treating tuberculosis: (isoniazid, rifampicin)
  • Medicines for treating depression and convulsions: Barbiturics (used as hypnotics, sedatives, and anticonvulsants)
  • Medicines to lower cholesterol levels in blood: (cholestyramine)
  • Medicines used to increase urine elimination (loop diuretics such as furosemide)
  • Medicines used for the treatment of gout (probenecid and sulfinpyrazone)
  • Medicines used to prevent nausea and vomiting: Metoclopramide and domperidone
  • Medicines used for the treatment of high blood pressure and heart rhythm disorders (arrhythmias): Propranolol.

Do not use with other analgesics (pain-relieving medicines) without consulting your doctor.

Tell your doctor or pharmacist if you are taking:

Flucloxacillin (antibiotic), due to a serious risk of blood and fluid anomaly (called metabolic acidosis) that requires urgent treatment (see section 2).

As a general rule for any medicine, it is recommended to systematically inform your doctor or pharmacist if you are being treated with another medicine. In the case of treatment with oral anticoagulants, it can be administered occasionally as the analgesic of choice.

Interference with analytical tests:

If you are going to have any analytical test (including blood tests, urine tests, skin tests that use allergens, etc.), tell your doctor that you are taking this medicine, as it may alter the results of these tests.

Calthek with food and drinks:

The use of paracetamol in patients who habitually consume alcohol (three or more alcoholic beverages per day: beer, wine, liquor...) may cause liver damage.

Taking this medicine with food does not affect its efficacy.

Use in children and adolescents:

Do not use in children or adolescents under 15 years of age.

Pregnancy and breastfeeding

If you are pregnant or breastfeeding, or think you may be pregnant or are planning to become pregnant, consult your doctor or pharmacist before using this medicine.

In case of need, paracetamol can be used during pregnancy. You should use the lowest possible dose that reduces pain or fever and use it for the shortest possible time. Contact your doctor if the pain or fever does not decrease or if you need to take the medicine more frequently.

Small amounts of paracetamol may appear in breast milk, therefore, it is recommended that you consult your doctor or pharmacist before taking this medicine.

Driving and using machines

The influence of paracetamol on the ability to drive and use machines is nil or insignificant.

3. How to take Calthek

Follow exactly the administration instructions of this medicine contained in this leaflet or as indicated by your doctor or pharmacist. In case of doubt, ask your doctor or pharmacist.

This medicine should be taken orally.

According to your preferences, the tablets can be swallowed directly or broken in half, with the help of a glass of liquid, preferably water. The score line is only for breaking the tablet if you find it difficult to swallow it whole.

Always use the lowest effective dose.

Avoid using high daily doses of paracetamol for prolonged periods, as this increases the risk of adverse effects such as liver damage.

The administration of this medicine is subject to the appearance of pain or fever. As these disappear, treatment should be discontinued.

If the pain persists for more than 5 days, the fever for more than 3 days, or the pain or fever worsens or other symptoms appear, you should discontinue treatment and consult your doctor.

The recommended dose is:

Adults and adolescents over 15 years of age with a weight over 50 kg: take 1 tablet every 4 or 6 hours, as needed. Do not take more than 3 tablets in 24 hours, divided into 3 doses.

Patient with liver disease: before taking this medicine, they must consult their doctor. They should take the amount of medicine prescribed by their doctor with a minimum interval of 8 hours between each dose. Do not take more than 3 tablets in 24 hours, divided into 3 doses.

Patient with kidney disease: before taking this medicine, they must consult their doctor.

Patient with severe or moderate disease may take a maximum of 500 mg of paracetamol per dose. Due to the paracetamol content, this medicine should not be used in these patients.

Elderly patients: should consult their doctor.

Use in children and adolescents:

Do not use in children (under 12 years) or adolescents with a body weight <50kg, as there are other formulations that allow for appropriate dosing for this group of patients.

If you think the action of this medicine is too strong or too weak, tell your doctor or pharmacist.

If you take more Calthek than you should:

You should consult your doctor or pharmacist immediately. In case of overdose or accidental ingestion, go immediately to a medical center or call the Toxicology Information Service (telephone 91 562 04 20), indicating the medicine and the amount taken.

If you have ingested an overdose, you should go immediately to a medical center, even if you do not notice symptoms, as they often do not appear until 3 days after ingestion, even in cases of severe poisoning.

The symptoms of overdose may be: dizziness, vomiting, loss of appetite, yellowing of the skin and eyes (jaundice), and abdominal pain.

Treatment of overdose is more effective if started within 4 hours of ingestion of the medicine.

Patient treated with barbiturics or chronic alcoholics may be more susceptible to the toxicity of a paracetamol overdose.

If you forget to take Calthek:

Do not take a double dose to make up for forgotten doses, simply take the forgotten dose when you remember, taking the next doses with the indicated interval between doses (at least 4 hours).

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.

Rare side effects that may occur (up to 1 in 1,000 people) are: discomfort, low blood pressure (hypotension), and increased levels of transaminases in the blood.

Very rare side effects that may occur (up to 1 in 10,000 people) are:

Kidney disease, cloudy urine, allergic dermatitis (skin rash), jaundice (yellowing of the skin), blood disorders (agranulocytosis, leucopenia, neutropenia, hemolytic anemia), and low blood sugar (hypoglycemia).

Very rare cases of severe skin reactions have been reported.

Frequency not known (cannot be estimated from the available data):

A serious disease that can make the blood more acidic (called metabolic acidosis) in patients with severe disease using paracetamol (see section 2).

Paracetamol may damage the liver when taken in high doses or for prolonged treatments.

Reporting of side effects:

If you experience any side effect, consult your doctor or pharmacist, even if it is a possible side effect not listed in this leaflet. You can also report them directly through the Spanish Pharmacovigilance System for Human Use Medicines: https://www.notificaram.es. By reporting side effects, you can help provide more information on the safety of this medicine.

5. Storage of Calthek

This medicine does not require special storage conditions.

Keep this medicine out of the sight and reach of children.

Do not use this medicine after the expiry date stated on the packaging. The expiry date is the last day of the month indicated.

“Medicines should not be disposed of via wastewater or household waste. Dispose of the packaging and any unused medicine in the SIGRE point of the pharmacy. If in doubt, ask your pharmacist how to dispose of the packaging and any unused medicine. This will help protect the environment.”

6. Contents of the pack and further information

Composition of Calthek

The active ingredient is paracetamol. Each tablet contains 650 mg of paracetamol.

The other ingredients are: pregelatinized corn starch, stearic acid, povidone, crospovidone, microcrystalline cellulose, and vegetable magnesium stearate.

Appearance of Calthek and pack contents

White, oblong, scored tablets, packaged in PVC/PVDC-Aluminum blisters.

This medicine is available in packs of 20 tablets.

Marketing authorization holder

Apotheke Laboratorios, S.L.

Paseo de la Castellana 40, 8th floor

28046 - Madrid

Spain

Manufacturer

Toll Manufacturing Services S.L

c/ Aragoneses, 2. 28108 Alcobendas (Madrid)

Spain

or

Farmalider S.A.

c/ Aragoneses, 2. 28108 Alcobendas (Madrid)

Spain

Date of the last revision of this leaflet:March 2025

“Detailed and updated information on this medicine is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) http://www.aemps.gob.es/”

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